The present invention relates to irrigation, and more particularly, to an improved electronic irrigation controller adapted primarily for lawn and garden irrigation which is easier to program and more flexible than prior irrigation controllers.
Most lawn and garden irrigation controllers which have heretofore been commercialized have depended upon "programs" which have been set up by the operator to initiate watering times at particular valve stations at a certain time of the day. The length of the watering cycle or run time must somehow be calculated by the operator and entered into the controller for each station. This may involve calculating two or more start times per station per day. This process is often complicated by confusing and cumbersome controller keyboards, entry switches, and operational programs. Even the most sophisticated solid state irrigation controllers have utilized several switches and indicators which often have multiple functions assigned to them.
A significant advance in the irrigation controller field is disclosed in U.S. Pat. No. 5,097,861 of Hopkins, et al. entitled "IRRIGATION METHOD AND CONTROL SYSTEM". That patent is assigned to Hunter Industries of San Marcos, Calif., the assignee of this patent application. The irrigation controller of said U.S. Pat. No. 5,097,861 can be programmed with a non-watering period for each watering station to thereby determine an available watering period for each watering station. Each watering station is thereafter only actuated within its corresponding available watering period in accordance with stored monthly mean temperature and evapotranspiration rates for the ZIP Code location of the irrigation controller. The input from a rain gauge connected to the irrigation controller can cause the watering schedules to either be suspended or recalculated. The irrigation controller of Hopkins, et al. also uses a signal from a thermometer as a factor in calculating sprinkler valve ON time. A single rotary switch which may also be pressed is utilized to program the irrigation controller through a hierarchy of menu structures shown on an LCD display. While the irrigation controller of said U.S. Pat. No. 5,097,861 has been a commercial success, it has been determined that further advancements in the irrigation controller art would be beneficial to homeowners, business property owners, apartment owners and golf course owners, desiring easier programming and more flexible capabilities.